JP2002326368A - Ink tank - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink tank which has a good ink volume efficiency with respect to the whole volume and is capable of relatively freely configuring a thick ink container. SOLUTION: In an ink tank 1, an ink container 3 filled with ink is accommodated inside a rigid container 2.
The ink container 3 has a cylindrical body 13 made of a flexible material.
First and second end plate members 11 and 12 for closing the opening portions 15 and 16 in a liquid-tight state,
And a coil spring 14 for expanding the second end plate members 11 and 12 with a predetermined spring force. Compared to a conventional flat ink bag made only of a flexible material, the ink container 3 having an arbitrary thickness can be easily configured,
It is easy to maintain the back pressure in an appropriate state. Therefore, an ink tank with good volume efficiency can be realized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink tank used as an ink supply source for an ink-jet printer or the like, and more particularly to an ink tank having a high volumetric efficiency (a high ratio of an ink storage amount to an occupied space). Things.

[0002]

2. Description of the Related Art As an ink tank mounted on an ink jet printer or the like, a so-called foam type in which a porous material such as a sponge impregnated with ink is accommodated in a rigid container, or a volume type corresponding to consumption of ink is used. There is known a configuration in which a flat ink bag formed of a flexible thin film is accommodated in a flat rigid container so as to reduce the pressure. In addition, as disclosed in JP-A-5-201019 and JP-A-6-320728, a part of a flat rigid container containing a flat ink bag therein is turned out of plane by attaching a film. There is also known a configuration having a side wall portion that can be elastically deformed.

[0003]

However, the conventional ink tank has the following problems. First, in the foam type ink tank, the solvent used when forming the foam impregnated with the ink, the foaming agent, and the like are slightly left as they are, and these are eluted into the ink, and the ink characteristics deteriorate. There is a risk. Also, the foam has been degassed, but there is a slight residual air,
This may be mixed into the ink, penetrate into the ink jet head together with the ink, and cause deterioration of the ink ejection characteristics. Further, components such as a surfactant contained in the ink may be absorbed by the foam, and the ink characteristics may be deteriorated.

Next, in an ink tank having a flat rigid container in which a flat ink bag made of a flexible material is housed, the amount of deformation of the ink bag is reduced as much as possible in order to obtain an appropriate back pressure. Like that. That is, the ink bag receives the ink suction pressure of the inkjet head (generally, the capillary force of the ink nozzle, -2 to 300).
It is necessary to generate a negative pressure within a deformable range at its own elastic force. However, when the shape of the ink bag is thickened, the amount of deformation of the ink bag accompanying consumption of the ink increases, and therefore, it is necessary to maintain the back pressure at an appropriate value during the period from when the ink is full to when the ink is exhausted. Have difficulty. For this reason, the ink bag must be formed in a flat shape, and the degree of freedom of the shape is small.

Further, in the ink tank having the structure disclosed in the above publication, an appropriate back pressure is maintained by deformation of a film attached to a rigid container. However, in this configuration, since the amount of deformation of the film in the out-of-plane direction is small, it can be applied to a flat ink tank.
For example, it cannot be applied to a thick ink tank having a shape close to a square.

In addition, the conventional ink tank has a low ink holding amount of about 40% of the entire volume (occupied area) of the ink tank. That is, the volumetric efficiency of the ink is low. Therefore, if an attempt is made to increase the ink holding amount, the size of the ink tank becomes large, which is disadvantageous for downsizing the ink jet printer.

[0007] In view of the above, the object of the present invention is to provide:
An object of the present invention is to propose an ink tank that can supply ink at a stable ink supply pressure and that can have a relatively free shape.

Another object of the present invention is to propose an ink tank which does not cause deterioration of ink characteristics in the case of a foam type ink tank.

Another object of the present invention is to propose an ink tank having a high volumetric efficiency of ink with respect to the entire volume.

[0010]

In order to solve the above-mentioned problems, an ink tank according to the present invention comprises a rigid container, an ink container accommodated in the rigid container, and a filling member in the ink container. An ink take-out hole for taking out the ink outside the rigid container, and an air communication hole that opens the inside of the rigid container to the atmosphere, wherein the ink containing portion is a rigid body disposed to face the rigid container. There are certain first and second end plate members, and a tubular body made of a flexible film and having both ends opened. The openings at both ends of the tubular body are the first and second ends, respectively. It is characterized by being sealed in a liquid-tight state by a plate member.

[0011] In the ink tank of this configuration, the ink accommodating portion accommodated in the rigid container is formed of a pair of end plate members and a cylinder made of a flexible material whose both ends are closed by the pair of end plate members. And a torso-shaped body. As the ink is consumed, the cylindrical body is crushed with the consumption of ink, and the pair of end plate members gradually approach each other, so that the thickness of the ink storage unit becomes thinner. Therefore, unlike the case of an ink bag made of a flexible material, an ink container having a thick shape close to a square can be formed, and the back pressure can be easily managed.
Further, since the ink storage portion can be formed into a similar shape having substantially the same size as the internal space of the rigid container, the volume efficiency of the ink can be increased. Furthermore, there is no deterioration in ink characteristics as in the case of a foam type ink tank.

Here, in order to make the deformation of the ink accommodating portion accompanying the ink consumption smooth, the first end plate member is fixed to the rigid container, and the second end plate member is made movable. It is desirable to keep it.

In this case, the ink ejection hole is formed so as to penetrate the first end plate member.

Further, instead of using the first end plate member as an independent member, an end plate portion functioning as the first end plate member may be integrally formed on a wall portion of the rigid container.
In this case, the ink ejection hole may be formed so as to penetrate the end plate portion.

Next, a filter for capturing foreign matter mixed in the ink and preventing entry of air bubbles is attached to an internal communication port communicating with the inside of the ink storage portion in the ink extraction hole. It is desirable.

On the other hand, the thickness of the ink container,
And when the distance between the second end plate members is increased, etc.
When a large back pressure is required, it is desirable to have a spring member that applies a spring force in a direction to separate the first and second end plate members from each other. Further, the spring member is desirable because it also functions as a member for maintaining the shape of the ink containing section.

In this case, the spring member may be a coil spring disposed between the first and second end plate members inside the ink container.

The typical shape of the ink tank of the present invention is a rectangular parallelepiped or a cylinder. In the case of a rectangular parallelepiped, it is preferable that the outer shapes of the rigid container and the ink containing section are rectangular parallelepiped, and in the case of a cylindrical body, it is preferable that both of them are cylindrical.

Next, in the ink tank of the present invention, the flexible film forming the cylindrical body may be a vapor-deposited film obtained by vapor-depositing a metal material or an inorganic material on a resin thin film.

Here, the deposited film is a polyethylene or polypropylene inner resin thin film, a polyethylene terephthalate outer resin thin film, and a composite deposited film in which a metal or inorganic material is deposited between the inner resin thin film and the outer resin thin film. can do. In this case, the inner resin thin film may be disposed so as to face the inside of the ink containing section.

Further, aluminum can be used as the metal material to be deposited.

Instead of using a vapor-deposited film, the flexible film forming the cylindrical body may be an elastic thin film made of an elastic material such as rubber or elastomer.

On the other hand, the attachment of the first and second end plate members to the cylindrical body constituting the ink containing section is desirably performed as follows. In other words, the first and second end portions of the cylindrical body wrap around the outer peripheral side surfaces of the first and second end plate members, and the first and second end portions are attached to the cylindrical body.
And it is desirable to attach the second end plate member.

In this case, the opening edge portions at both ends of the cylindrical body and the outer peripheral side surfaces of the first and second end plate members can be fixed by bonding, fusion, or a packing ring.

[0025]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an example of an ink tank to which the present invention is applied will be described with reference to the drawings.

FIG. 1 is an exploded perspective view of the ink tank of this embodiment, and FIG. 2 is a schematic sectional view thereof. Explaining with reference to these drawings, the ink tank 1 of the present embodiment has a substantially cubic-shaped rigid container 2 and an ink container 3 accommodated therein. The ink 4 is stored inside. The rigid container 2 includes a container main body 5 having an open upper side, and a container lid 6 closing the opening of the container main body 5. An atmosphere communication hole 8 that opens the inside 7 of the rigid container 2 to the atmosphere is formed in the container lid 6. The rigid container 2 having this configuration is a molded product of a synthetic resin material such as PET.

The ink container 3 has a substantially cubic shape having substantially the same size as the inside 6 of the rigid container, and has a first end plate member 11 having a substantially square shape and a second end plate member having the same shape. A member 12, a tubular body 13 having a rectangular cross-section and having both ends opened and made of a flexible thin film; first and second end plate members 11;
The coil spring 14 is disposed between the coil springs 12.

The opening 15 at one end of the cylindrical body 13 is the first
The opening 16 at the other end is similarly sealed in a liquid-tight state by the second end plate member 12. In the present example, the inner side surface of the opening edge portion 15a is in the first state in a state where the opening edge portion 15a on the side of the opening portion 15 of the cylindrical body portion 13 wraps around the four peripheral side surfaces 11a of the first end plate member 11. Four circumferential side surfaces 11 of end plate member 11
a is fixed by adhesion or fusion-fixed to the substrate a. Similarly, the opening edge portion 16a of the other opening 16 of the cylindrical body 13 also covers the four peripheral side surfaces 12a of the second end plate member 12, and the inner peripheral surface of the opening edge portion 16a
Are fixed to the four peripheral side surfaces 12a of the end plate member 12 by adhesive bonding or fusion bonding.

Thus, the cylindrical body 13 and the first,
The ink 4 is stored in a substantially cubic ink storage portion formed by the second end plate members 11 and 12. In addition, a coil spring 14 is provided inside the ink container.
Are arranged, one end of which is fixed to the first end plate member 11 and the other end of which is fixed to the second end plate member 12, and the first and second end plate members are fixed by a constant spring force. 1
It is always biased in the direction away from 1 and 12.

Here, in this example, the first end plate member 11 located on the lower side is fixed to the flat bottom surface 5a of the container body 5 with an adhesive or the like. On the other hand, the second end plate member 12 located on the upper side can move up and down inside the ink storage unit. Fixed-side first end plate member 1
1 and the container bottom plate portion 5b are provided with ink ejection holes 17 penetrating them. A filter 18 is attached to an inner communication port 17a of the ink outlet 17 which communicates with the inside of the ink container. The filter 18 captures foreign matter mixed in the ink, and prevents the passage of air bubbles. A valve member 19 for preventing ink leakage is attached to a portion of the ink ejection hole 17 on the side of the outer communication port 17b.

The first end plate member 11 fixed to the container body 5 is not prepared as an independent member, but an end plate portion functioning as the first end plate member 11 is provided on the bottom plate portion 5b of the container body 5. May be integrally formed.

Next, the flexible film forming the cylindrical body 13 is a vapor-deposited film in which a metal material or an inorganic material is vapor-deposited on a resin thin film. In this example, this deposited film is a composite deposited film in which a metal material or an inorganic material is deposited between the inner resin thin film and the outer resin thin film, and the inner resin thin film of polyethylene or polypropylene, the outer resin thin film of polyethylene terephthalate. . Aluminum can be used as the metal material, and silica or the like can be used as the inorganic material. In the case of the composite vapor-deposited film having this configuration, it may be arranged so that the inner resin thin film faces the inside of the ink containing section.

Instead of the composite vapor-deposited film, the flexible film forming the cylindrical body 13 may be an elastic thin film made of an elastic material such as rubber or elastomer.

The ink tank 1 according to the present embodiment thus configured
Is mounted on the side of the ink jet printer, the ink supply needle of the ink jet printer is inserted into the ink ejection hole 17 to form an ink supply path to the ink jet head. When ink droplets are ejected from the ink nozzles of the inkjet head, a negative pressure is generated in the ink outlet 17 by the ejection pressure, and ink is supplied from inside the ink storage unit 3.

As the ink is consumed, the movable second end plate member 12 approaches the first end plate member 11 against the spring force as shown in FIG. Gradually decreases. In a state where the ink has run out, the movable second end plate member 12 is in a state of being closest to the first end plate member 11.

The ink tank 1 according to the present embodiment thus configured
In the first embodiment, the ink storage unit 3 includes first and second rigid end plate members 11 and 12 and a flexible cylindrical body 13. Therefore, unlike a conventional ink bag made of only a flexible material, the amount of deformation can be increased, and an appropriate negative pressure (back pressure) state can be easily maintained. Therefore, it is easy to match the shape of the ink container 3 to the shape of the rigid container 2, and the volume efficiency can be increased. In addition, the shape of the ink container can be set relatively freely, and a thick ink container can be formed.

The first and second end plate members 11, 1
By appropriately setting the spring characteristics of the coil spring 14 disposed between the two, the back pressure of the ink containing section 3 can be set to an appropriate state. In addition, by disposing the coil spring 14, the first and second end plate members 11, 12
Even when the distance is large, the shape of the ink containing section 3 can be maintained.

Further, there is no adverse effect such as deterioration of ink characteristics as in the case of a foam type ink tank.

In addition, since the ink container 3 is covered with the rigid container 2, there are the following advantages. For example, when the cylindrical body portion 13 of the ink container 3 is formed using a flexible material having a structure in which aluminum is deposited on a resin thin film, the flexible material has many pinholes. Water vapor is released through them. But,
The water vapor released from the ink storage unit 3 accumulates in the space between the ink storage unit 3 and the rigid container 2, and the space is almost saturated with the water vapor. As a result, evaporation of water from the filled ink can be suppressed, and a change in physical properties of the ink can be prevented.

In this embodiment, the cylindrical body 13 made of a flexible material is bonded or fixed to the first and second end plate members 11 and 12 by using a packing ring or the like. May be fixed by using the sealing tool. For example, FIG.
As shown in FIG. 1, in order to form the cylindrical ink storage portion 3A, the first and second disk-shaped end plate members 11A and 11A are formed.
2A can be attached in a liquid-tight manner to the openings at both ends of the cylindrical body 13A having a circular cross section using the packing rings 20A and 20B. In this case, if a groove 51 is formed on the outer peripheral surface of each end plate member 11A, 12A and the projection on the side of the packing rings 20A, 20B is fitted therein, a liquid-tight state is reliably formed. it can.

[0041]

As described above, in the ink tank of the present invention, the ink container filled with ink is accommodated in the rigid container, and the ink container is formed into a cylindrical body made of a flexible material. And a first for closing the openings at both ends in a liquid-tight state.
And a second end plate member.

Therefore, according to the present invention, unlike a conventional ink bag made of only a flexible material, the ink container having a thick shape can be easily formed while maintaining a proper back pressure. Can be configured. As a result, it is possible to realize an ink tank having higher volume efficiency than the conventional one. Further, there is no adverse effect such as deterioration of ink characteristics as in the case of a foam type ink tank.

[Brief description of the drawings]

FIG. 1 is a perspective view illustrating an example of an ink tank to which the present invention is applied.

FIG. 2 is a schematic sectional view of the ink tank of FIG.

FIG. 3 is an explanatory diagram showing a state in which the volume of the ink storage unit of the ink tank in FIG. 1 has been reduced with the consumption of ink.

FIG. 4 is a perspective view and a partial cross-sectional view illustrating another example of the ink storage unit in FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ink tank 2 Rigid container 3, 3A Ink storage part 4 Ink 5 Container main body 5a Bottom surface 5b Bottom plate part 6 Container lid 7 Inside of rigid container 8 Atmospheric communication hole 11, 11A First end plate member 11a Outer side surface 12, 12A Second End plate member 12a Outer peripheral side surface 13 and 13A Ink storage portion 14 Coil spring 15 First end plate member 15a Four peripheral side surface 16 Second end plate member 16a Four peripheral side surface 17 Ink ejection hole 18 Filter 20A, 20B Packing ring

Claims (14)

[Claims] 1. A rigid container, an ink container accommodated in the rigid container, an ink ejection hole for ejecting ink filled in the ink container to the outside of the rigid container, An air communication hole that opens the inside of the rigid container to the atmosphere, wherein the ink container has first and second end plate members, which are rigid bodies opposed to each other, and both ends formed of a flexible film. An ink tank, comprising: an open tubular body, wherein openings at both ends of the tubular body are closed in a liquid-tight state by the first and second end plate members, respectively. 2. The ink tank according to claim 1, wherein the first end plate member is fixed to the rigid container, and the second end plate member is held in a movable state. 3. The ink tank according to claim 2, wherein the ink ejection hole is formed so as to penetrate the first end plate member. 4. The rigid container according to claim 2, wherein an end plate portion functioning as the first end plate member is integrally formed on a wall surface portion of the rigid container, and the end plate portion penetrates through the end plate portion. An ink tank having an ink ejection hole formed therein. 5. The ink supply device according to claim 1, wherein the internal communication port of the ink ejection hole communicating with the inside of the ink storage portion captures foreign matter mixed in the ink and prevents the intrusion of bubbles. An ink tank, wherein the filter is attached. 6. The ink tank according to claim 1, further comprising: a spring member that applies a spring force in a direction separating the first and second end plate members from each other. 7. The ink tank according to claim 6, wherein the spring member is a coil spring disposed between the first and second end plate members inside the ink container. 8. The method according to claim 1, wherein the outer shape of the rigid container and the ink container is a rectangular parallelepiped,
Alternatively, the ink tank is a cylindrical body. 9. The ink tank according to claim 1, wherein the flexible film forming the cylindrical body is formed by depositing a metal material or an inorganic material on a resin thin film. 10. The flexible film according to claim 9, wherein the flexible film is an inner resin thin film of polyethylene or polypropylene, an outer resin thin film of polyethylene terephthalate, and a metal or inorganic material between the inner resin thin film and the outer resin thin film. An ink tank, which is a composite vapor-deposited film, wherein the inner resin thin film is disposed so as to face the inside of the ink storage unit. 11. The ink tank according to claim 9, wherein the metal material is aluminum. 12. The ink tank according to claim 1, wherein the flexible film forming the cylindrical body is an elastic thin film made of an elastic material such as rubber or elastomer. 13. The cylindrical body according to claim 1, wherein both ends of the cylindrical body are open at the first and second ends.
An ink tank, wherein the first and second end plate members are attached to the cylindrical body in a state of wrapping the outer peripheral side surface of the end plate member. 14. The device according to claim 13, wherein the opening edge portions at both ends of the cylindrical body and the outer peripheral side surfaces of the first and second end plate members are fixed by bonding, fusion, or a packing ring. An ink tank characterized by: